package main

import "fmt"

func reverseString(s []byte) {
	var r byte
	l := len(s)
	for i := 0; i < l/2; i++ {
		r = s[i]
		s[i] = s[l-1-i]
		s[l-1-i] = r
	}
	fmt.Printf("%s\n", s)
}
